/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

/* 容器样式 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* 头部样式 */
header {
    background-color: #fff;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 15px 0;
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 24px;
    font-weight: bold;
    color: #2c3e50;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
}

nav a {
    text-decoration: none;
    color: #555;
    padding: 8px 16px;
    border-radius: 4px;
    transition: all 0.3s ease;
}

nav a:hover {
    color: #3498db;
}

nav a.active {
    background-color: #3498db;
    color: white;
}

/* 主页样式 */
.hero {
    text-align: center;
    margin: 50px 0;
}

.hero h2 {
    font-size: 36px;
    margin-bottom: 15px;
    color: #2c3e50;
}

.hero p {
    font-size: 18px;
    color: #7f8c8d;
    margin-bottom: 30px;
}

.buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

/* 按钮样式 */
.btn-primary, .btn-secondary {
    display: inline-block;
    padding: 12px 30px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    font-size: 16px;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background-color: #3498db;
    color: white;
}

.btn-primary:hover {
    background-color: #2980b9;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.btn-secondary {
    background-color: #ecf0f1;
    color: #34495e;
    border: 2px solid #bdc3c7;
}

.btn-secondary:hover {
    background-color: #bdc3c7;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

/* 仪表盘样式 */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin: 30px 0;
}

.stat-card {
    background-color: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

.stat-card h3 {
    color: #7f8c8d;
    font-size: 16px;
    margin-bottom: 10px;
}

.stat-number {
    font-size: 32px;
    font-weight: bold;
    color: #2c3e50;
    margin-bottom: 8px;
}

.stat-change {
    font-size: 14px;
    padding: 2px 8px;
    border-radius: 12px;
}

.stat-change.positive {
    background-color: #d4edda;
    color: #155724;
}

.stat-change.negative {
    background-color: #f8d7da;
    color: #721c24;
}

.charts {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 30px;
    margin: 40px 0;
}

.chart-container {
    background-color: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

.chart-container h3 {
    margin-bottom: 20px;
    color: #2c3e50;
}

.chart-placeholder {
    height: 200px;
    background-color: #f8f9fa;
    border-radius: 5px;
    position: relative;
}

.chart-placeholder::after {
    content: "图表区域";
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #999;
}

.recent-activities {
    background-color: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

.activity-list {
    margin-top: 20px;
}

.activity-item {
    display: flex;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid #eee;
}

.activity-item:last-child {
    border-bottom: none;
}

.activity-time {
    color: #7f8c8d;
    font-size: 14px;
}

/* 个人信息页面样式 */
.auth-container {
    max-width: 500px;
    margin: 50px auto;
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.1);
    overflow: hidden;
}

.auth-tabs {
    display: flex;
    border-bottom: 1px solid #eee;
}

.tab-btn {
    flex: 1;
    padding: 15px;
    background: none;
    border: none;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
    color: #555;
}

.tab-btn:hover {
    background-color: #f8f9fa;
}

.tab-btn.active {
    background-color: #3498db;
    color: white;
}

.auth-form {
    padding: 30px;
    display: none;
}

.auth-form.active {
    display: block;
}

.auth-form h2 {
    margin-bottom: 25px;
    text-align: center;
    color: #2c3e50;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
    transition: border-color 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: #3498db;
}

/* 页脚样式 */
footer {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px 0;
    margin-top: 50px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    nav {
        flex-direction: column;
        gap: 15px;
    }
    
    .buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .stats {
        grid-template-columns: 1fr;
    }
    
    .charts {
        grid-template-columns: 1fr;
    }
    
    .chart-container {
        min-width: auto;
    }
}